Euarthropoda
   †Lamellipedia see Superclass Lamellipedia Hou & Bergström, 1997
     †Artiopoda Hou & Bergström, 1997 see Subphylum Artiopoda Hou & Bergström, 1997
       †Retifaciida see Order Retifaciida Hou & Bergström, 1997
         1 Genus †Pygmaclypeatus Zhang, Han & Shu, 2000
         2 Genus †Retifacies Hou, Chen & Lu, 1989